2 * Copyright (c) 2011 Fabien Thomas <fabient@FreeBSD.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
31 #include <sys/kernel.h>
32 #include <sys/module.h>
33 #include <sys/systm.h>
35 #include <machine/bus.h>
37 #include <machine/resource.h>
38 #include <sys/watchdog.h>
40 #include <isa/isavar.h>
41 #include <dev/pci/pcivar.h>
45 #define viawd_read_4(sc, off) bus_read_4((sc)->wd_res, (off))
46 #define viawd_write_4(sc, off, val) \
47 bus_write_4((sc)->wd_res, (off), (val))
49 static struct viawd_device viawd_devices[] = {
50 { DEVICEID_VT8251, "VIA VT8251 watchdog timer" },
51 { DEVICEID_CX700, "VIA CX700 watchdog timer" },
52 { DEVICEID_VX800, "VIA VX800 watchdog timer" },
53 { DEVICEID_VX855, "VIA VX855 watchdog timer" },
54 { DEVICEID_VX900, "VIA VX900 watchdog timer" },
58 static devclass_t viawd_devclass;
61 viawd_tmr_state(struct viawd_softc *sc, int enable)
65 reg = viawd_read_4(sc, VIAWD_MEM_CTRL);
67 reg |= VIAWD_MEM_CTRL_TRIGGER | VIAWD_MEM_CTRL_ENABLE;
69 reg &= ~VIAWD_MEM_CTRL_ENABLE;
70 viawd_write_4(sc, VIAWD_MEM_CTRL, reg);
74 viawd_tmr_set(struct viawd_softc *sc, unsigned int timeout)
77 /* Keep value in range. */
78 if (timeout < VIAWD_MEM_COUNT_MIN)
79 timeout = VIAWD_MEM_COUNT_MIN;
80 else if (timeout > VIAWD_MEM_COUNT_MAX)
81 timeout = VIAWD_MEM_COUNT_MAX;
83 viawd_write_4(sc, VIAWD_MEM_COUNT, timeout);
84 sc->timeout = timeout;
88 * Watchdog event handler - called by the framework to enable or disable
89 * the watchdog or change the initial timeout value.
92 viawd_event(void *arg, unsigned int cmd, int *error)
94 struct viawd_softc *sc = arg;
97 /* Convert from power-of-two-ns to second. */
99 timeout = ((uint64_t)1 << cmd) / 1000000000;
101 if (timeout != sc->timeout)
102 viawd_tmr_set(sc, timeout);
103 viawd_tmr_state(sc, 1);
106 viawd_tmr_state(sc, 0);
109 /* Look for a supported VIA south bridge. */
110 static struct viawd_device *
111 viawd_find(device_t dev)
113 struct viawd_device *id;
115 if (pci_get_vendor(dev) != VENDORID_VIA)
117 for (id = viawd_devices; id->desc != NULL; id++)
118 if (pci_get_device(dev) == id->device)
124 viawd_identify(driver_t *driver, device_t parent)
127 if (viawd_find(parent) == NULL)
130 if (device_find_child(parent, driver->name, -1) == NULL)
131 BUS_ADD_CHILD(parent, 0, driver->name, 0);
135 viawd_probe(device_t dev)
137 struct viawd_device *id;
139 id = viawd_find(device_get_parent(dev));
140 KASSERT(id != NULL, ("parent should be a valid VIA SB"));
141 device_set_desc(dev, id->desc);
142 return (BUS_PROBE_GENERIC);
146 viawd_attach(device_t dev)
149 struct viawd_softc *sc;
150 uint32_t pmbase, reg;
152 sc = device_get_softc(dev);
155 sb_dev = device_get_parent(dev);
156 if (sb_dev == NULL) {
157 device_printf(dev, "Can not find watchdog device.\n");
162 /* Get watchdog memory base. */
163 pmbase = pci_read_config(sb_dev, VIAWD_CONFIG_BASE, 4);
166 "Watchdog disabled in BIOS or hardware\n");
170 /* Allocate I/O register space. */
172 sc->wd_res = bus_alloc_resource(dev, SYS_RES_MEMORY, &sc->wd_rid,
173 pmbase, pmbase + VIAWD_MEM_LEN - 1, VIAWD_MEM_LEN,
174 RF_ACTIVE | RF_SHAREABLE);
175 if (sc->wd_res == NULL) {
176 device_printf(dev, "Unable to map watchdog memory\n");
180 /* Check if watchdog fired last boot. */
181 reg = viawd_read_4(sc, VIAWD_MEM_CTRL);
182 if (reg & VIAWD_MEM_CTRL_FIRED) {
184 "ERROR: watchdog rebooted the system\n");
185 /* Reset bit state. */
186 viawd_write_4(sc, VIAWD_MEM_CTRL, reg);
189 /* Register the watchdog event handler. */
190 sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, viawd_event, sc, 0);
194 if (sc->wd_res != NULL)
195 bus_release_resource(dev, SYS_RES_MEMORY,
196 sc->wd_rid, sc->wd_res);
201 viawd_detach(device_t dev)
203 struct viawd_softc *sc;
206 sc = device_get_softc(dev);
208 /* Deregister event handler. */
209 if (sc->ev_tag != NULL)
210 EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
214 * Do not stop the watchdog on shutdown if active but bump the
215 * timer to avoid spurious reset.
217 reg = viawd_read_4(sc, VIAWD_MEM_CTRL);
218 if (reg & VIAWD_MEM_CTRL_ENABLE) {
219 viawd_tmr_set(sc, VIAWD_TIMEOUT_SHUTDOWN);
220 viawd_tmr_state(sc, 1);
222 "Keeping watchog alive during shutdown for %d seconds\n",
223 VIAWD_TIMEOUT_SHUTDOWN);
226 if (sc->wd_res != NULL)
227 bus_release_resource(sc->dev, SYS_RES_MEMORY,
228 sc->wd_rid, sc->wd_res);
233 static device_method_t viawd_methods[] = {
234 DEVMETHOD(device_identify, viawd_identify),
235 DEVMETHOD(device_probe, viawd_probe),
236 DEVMETHOD(device_attach, viawd_attach),
237 DEVMETHOD(device_detach, viawd_detach),
238 DEVMETHOD(device_shutdown, viawd_detach),
242 static driver_t viawd_driver = {
245 sizeof(struct viawd_softc),
248 DRIVER_MODULE(viawd, isab, viawd_driver, viawd_devclass, NULL, NULL);